Heat exchanger tube



FIG. 1 is a perspective view of a heat exchanger tube;

FIG. 2 is a front view thereof, the opposite side being an identical image of the side shown herein;

FIG. 3 is a left side view thereof, the opposite side being an identical image of the side shown herein; and,

FIG. 4 is a top view thereof.

In the drawings, the broken lines depict portions of the heat exchanger tube that are environmental subject matter only and form no part of the claimed design.

The dashed lines show a boundary between the claimed design and unclaimed portions. 

CLAIM The ornamental design for a heat exchanger tube, as shown and described. 